WASHINGTON — Six years after his mysterious death in a Moscow prison cell, Sergei L. Magnitsky has become a byword for brutality in President Vladimir V. Putin’s Russia. Now, a documentary film that paints Mr. Magnitsky as an accomplice rather than a victim is generating a furor, with critics trying to block a screening of it next week in Washington.
Screenings of the film, “The Magnitsky Act — Behind the Scenes,” have been canceled in Europe after threats of libel suits from William F. Browder, an American-born financier who fell afoul of the Russian government and hired Mr. Magnitsky, a lawyer and auditor, to investigate a vast tax fraud scheme after the government seized three of his Russian subsidiaries.
“The Magnitsky Act” is to be screened on Monday at the Newseum, a private museum dedicated to the news industry. Lawyers for Mr. Browder and Mr. Magnitsky’s mother, Natalia Magnitskaya, sent a letter to the Newseum this week demanding that it call off the event. After a conference call on Thursday, the museum’s management refused.
“We stand for free speech and free expression,” said Scott Williams, the chief operating officer of the Newseum. “We’re not going to allow them not to show the film.” He noted that the museum was not sponsoring the screening, but merely renting out its theater. “We often have people renting for events that other people would love not to have happen,” he said.
Mr. Browder, who lives in London, has accused the film’s director, Andrei Nekrasov, of defaming him and smearing the memory of Mr. Magnitsky. The film asserts that the widely accepted version of Mr. Magnitsky’s death is wrong: that the police did not beat him before he died, and that he did not testify that the police had conspired to steal $230 million in fraudulent tax rebates. Indeed, the film says it was Mr. Browder who orchestrated the fraud.
The legacy of Mr. Magnitsky, who was 37 at the time of his death, is complicated because he has become such a potent symbol. In 2012, Congress passed a law bearing his name that blacklisted Russian officials involved in human-rights abuses. The Kremlin retaliated by imposing sanctions on several American citizens and banning the adoption of Russian children by Americans.
Lawmakers are now trying to pass legislation that would impose sanctions on people anywhere in the world for the kinds of human-rights abuses that surfaced in the Magnitsky case. Much to the frustration of the Russian government, the bill would again bear his name. A screening at the Newseum is especially controversial because it could attract lawmakers or their aides. The cavernous museum, which sits on Pennsylvania Avenue in the shadow of the Capitol, has the text of the First Amendment etched above its main entrance.
Mr. Nekrasov is an experienced documentary maker whose work has sometimes been critical of the Russian government. He made films about the Russian crackdown in Chechnya and the poisoning of Alexander V. Litvinenko, a former intelligence officer.
Speaking from Berlin, Mr. Nekrasov said he had not begun the project intending to undermine the account of Mr. Magnitsky’s death. He said that he viewed it more as a docudrama about Mr. Magnitsky’s last days, and that he had consulted Mr. Browder, whom he envisioned as the film’s narrator. But as he began scrutinizing original documents in the case, Mr. Nekrasov said, he began to doubt Mr. Browder’s version of events.
“It’s difficult to pin down the moment when I thought it was a lie, it’s a made-up story,” he said. One clue, he said, was that “there was no sign of whistle-blowing” on the part of Mr. Magnitsky.
People familiar with the Magnitsky case expressed doubt that he was in on a conspiracy. “When I was in the government,” said Michael A. McFaul, a former United States ambassador to Russia, “we studied closely his tragic case and had a radically different assessment.”
In April, a screening of the film at the European Parliament was called off at the last minute after lawyers for Mr. Browder threatened legal action. The British law firm Carter-Ruck also sent a letter to Arte, a German-French television network that planned to broadcast the film.
In the United States, Mr. Nekrasov has retained the Potomac Square Group, a small public affairs and lobbying firm that has worked for Bahrain, Kuwait and Azerbaijan, among other foreign governments. It is run by Christopher Cooper, a former Wall Street Journal reporter. Mr. Cooper rented the theater in the Newseum and declined to say who was paying his company. “I’m putting this event together for the director,” he said.
Mr. Cooper said there would be a question-and-answer session with Mr. Nekrasov, moderated by the investigative journalist Seymour Hersh, after the screening. The organizers considered inviting Mr. Browder to take part in the session, Mr. Cooper said, and might still do so.
Mr. Browder did not return requests for comment. But he has spoken out in the past against the film, calling it “a calculated attempt to harm our campaign and to make people doubt the legacy of Sergei Magnitsky.”
Lawyers for Mr. Browder have presented substantial documentary evidence, including photographs, that Mr. Magnitsky was beaten in his jail cell. They also cite transcripts of testimony in which he named police officers as being involved in the tax fraud.
That Mr. Magnitsky was mistreated in jail is hardly in dispute. The Russian authorities initially claimed he had died from sudden heart failure. But after persistent questions, Russia’s then-president, Dmitri A. Medvedev, ordered prosecutors to open an investigation.
In 2011, a human rights panel that advised Mr. Medvedev issued a report concluding that Mr. Magnitsky had been beaten. His health issues went untreated for the 11 months he was in custody. The report said that investigators and prison officials shared responsibility for his death.
Mr. Browder was once the largest foreign investor in Russia’s stock market. He defended Mr. Putin, and in 2005, he told a reporter that the newly elected president of Ukraine, Viktor A. Yushchenko, needed to cultivate closer ties with Russia. Since he was expelled from Russia, however, Mr. Browder has become a fierce crusader against official corruption there.
Last year, he published a book, “Red Notice: A True Story of High Finance, Murder and One Man’s Fight for Justice,” that delved into the circumstances of Mr. Magnitsky’s death.